Tuberous sclerosis (T.S.) is a genetic disorader with variable penetrance and expression known to affect a wide range of organs including brain, skin, kidneys, heart, and less frequenctly, the liver, spleen, adrenal glands, thyroid, lungs, GI tract, and bones. the cause of T.S. remains unknown. There have been no recent scientific meetings in which T.S. has been discussed in a comprehensive manner. The research workshop is designed to bring together leading clinicians and research scientists interested in T.S. in order to: --review currently available knowledge of the clinical, pathological, and genetic features of T.S.; --identify promising investigational techniques in cellular and molecular biology, biochemistry, and genetics; formulate research questions (which may be interdisciplinary in nature) relevant to T.S. and which may expected to lead to the development of specific research proposals. Minimal diagnostic criteria for T.S. will be discussed, and criteria for the development of an information set appropriate for a national T.S. registry will be developed. Development of a community of scholars interested in furthering the understanding of T.S. is of high priority. Information of clinical and research ideas discussed during the workshop will be disseminated in a publication of the workshop proceedings.